Tardif etal	def. pub.
usb of in-line mixer to uniformly disperse bubbles
throughout molten polyester prepolymer



266-50 SR F5200 XR T 8660017 DEFENSIVE PUBLICATION UNITED STATES PATENT OFFICE Published at the request of the applicant or owner in accordance with the Notice of Apr. 11, 1068, 840 0.6. 1221. lden tlticution is by serial number of the application and the heading indicates the number 0! pages of specification, Including claims, and of sheets 01' drawing contained in the application as originally flied. The tile of this nppllcntlon is available to the public for inspection; reproduction may be purchased for 80 centl per aheeti Applications published under the Defensive Publication Program have not been examined on to the merits 0t alleged invention. The Patent Olll e mn ites no assertion as to the novelty of the disclosed subject matter.

PUBLISHED SEPTEMBER iii, liiiifl 752,701 USE OF IN-LINE MIXER T0 UNIFORMLY DIS- PERSE BUBBLES THROUGHOUT MOLTEN POLY- ESTER PREPOLYMER Richard E. Tardif, Pittsford, N.Y. (1669 Lake Ave., Rochester, NY. 14650); and John W. Fitzgerald, 343 Stat SL; and Roy A. Le Blanc, 1669 Lake Ave., both of Rochester, N.Y. 14650 Filed Aug. 14, 1968. Published Sept. 16, 1969 Int. Cl. (308g 53/02 US. Cl. 260-25 2 Sheets Drawing. 6 Page! Specification It has been found that by the use of an in-linc motor having the ability to intensely agitate fluid molten relativly low molecular weight polymers such as prepolymeric poly(ethylene terephthalate) shortlyafter or at about the point where an inert gas is introduc'ed into the mo]- ten prcpolymer, bubbles of the inert gas can be dispprsed uniformly through the prepolyme'r. After the prepolymer containing the tiny bubbles is solidified, it is easier to grind.

FIGURE 1 denotes one way of carrying out the process. As illustrated, molten prepolyrn'er is directed through conduit '1, which is insulated to keep the prepolymnr molten, into close proximity to a means for agitating thc prepolymei (blhdes 3 utilized to shaft 2 which can bo driven at high speeds by any conventional means such as motor 4). While the molten prepolymer continues to flowandbeagitminertguisiniectndunderpnessure through line 8 and orifice 7 into close proximity to' the whirling blades 3, whereupon it is quickly dispersed uniformly through the molten prepolymor stream in the form of tiny bubbles. As a final step, the molten prepolyrner is conducted quickly away from the agitator and subjected to conditions below its melting point, preferably within about 30 seconds.

F5201) XR T 3660017 752 70! Sept. 16, 1969 R. E. TARDIF ET AL DE,F. PUB.

USE OF IN-LINE MIXER TO umronmm msmzasz Bunsuss THROUGHOUT MOLTEN POLYESTER PREPOLYMER 1 ml Aug. 14 19 5 2 Sheets-Sheet l JOHN m FITZGERALD ROY A. LeBL-ANC RICHARD E. TARP/F ATTORNEYS DEF. PUB.

Sept. 16, 1969 R. E. TARDIF ETAL USE OF IN-LINE MIXER TO UNIFORMLY DISPERSE BUBBLES THROUGHOUT MQLTEN POLYESTER PREPOLYMER 2 Sheets$heet 2 Filed Aug. 14 1968 FIG. 2

V 177 1/ i .F

JOHN W F! TZGERALD R0 Y A. LCBL ANG A TTORNE Y5 

